Personality is a topic that has been discussed for many years by a multitude of psychologists with numerous different opinions. Not only has there been the topic of personality but for more than 50 years psychologists have also tried to measure traits and states in order to discover more about personality’s structure, in addition to extending their knowledge of the FFT (Five-Factor Theory) which are five different essential traits (extroversion, neuroticism, openness to experience, agreeableness, and conscientiousness) of personality. Gordon W. Allport, Walter Mischel, Robert R. McCrae, and Paul T. Costa Jr. all talk about different aspects of personality within each of their articles, each aspect that is addressed plays a vital role in the continuing discovery of personality. Some of the aspects of personality discussed in their articles include, different criteria to define trait, the importance of correlation, and the four assumptions of human nature explicitly acknowledged by the FFT. Although Allport’s “What Is Trait Personality?”, Mischel’s "Consistency and Specificity in Behavior", and McCrae and Costa Jr.‘s “The Five Factor Theory of Personality” are about the trait theory of personality, all three articles also provide opposing views of personality. Allport presents the aid of criteria to help define trait throughout his article “What Is Trait Personality?” He believes traits are a very real and vital part of one's existence. He believes traits can be verified scientifically, and that they also tend to cut across situations and thereby account for the more permanent, enduring, and general features of our behavior, unlike habits that while enduring refer to more narrow and limited types of tendencies. In addition he believes traits to be dynamic such that they, underline behavior- they cause behavior. Allport believed that there is no rigid boundary separating one trait from another, rather that personality